徒勞無益

futile endeavor (idiom)

surname Tu

disciple / apprentice / believer / on foot / bare or empty / to no avail / only / prison sentence

disciple; apprentice; believer / on foot / bare; empty / to no avail / only / prison sentence

surname Yi

benefit / profit / advantage / beneficial / to increase / to add / all the more

not to have / no / none / not / to lack / un- / -less

to toil / labor / laborer / to put sb to trouble (of doing sth) / meritorious deed / to console (Taiwan pr. [lao4] for this sense)

futile

no good / not good for / not beneficial